Intertidal seagrass meadows in South west England: the ecological and socio-economic benefits of restoration

Project description:

Lush, intertidal seagrass meadows appear to be spreading in SW England estuaries, replacing harmful, smothering green macroalgae. How can we evidence the changes (locally/globally) and how important are these new estuarine habitats?

With a multidisciplinary team from PML, University of Plymouth, JNCC and Westcountry Rivers Trust you will do research that covers everything from satellites to drones, benthic invertebrates to birds, and ecosystem services to socio-economic impact to identify the value of intertidal seagrass restoration.

What are the causes and ecological implications of the change?

Climate change may be a factor, but also changes in agricultural land management to reduce nutrient loads in upstream waters that drain into estuaries.

Subtidal seagrass has high conservation importance. We know it has positive impacts on biodiversity and provides ecosystem services including blue carbon storage and a nursery ground for fish and shellfish.

In contrast, the ecosystem services from intertidal seagrass are unknown!

This exciting and novel PhD project will:

  • Provide evidence for the change in intertidal vegetation
  • Identify drivers for increases in intertidal seagrass meadows in SW England
  • Determine which factors can be managed to support seagrass restoration efforts elsewhere
  • Provide understanding of the ecological consequences of this change
  • Consider what ecosystem services are supported by intertidal seagrass and what are the implications of seagrass recovery for natural capital

This new knowledge will support and justify wider restoration and recovery of seagrasses.

You will receive training to take an interdisciplinary approach e.g.

  • Earth observation image delivery and analysis via satellites and aerial drones to identify extent and rate of development of seagrass.
  • Case studies to identify causes of development of meadows.
  • Benthic surveys and experiments.
  • Quantification of ecosystem services, including climate regulation.
  • Natural capital.
  • Potentially, use of drones to monitor intertidal seagrass through citizen science.
To do this project you will need: good understanding of marine and estuarine ecology and of basic biogeochemistry; basic skills to process data in R or Python; sufficient numeracy to be able to learn to analyse earth observation, ecological and ecosystem service data. Understanding of ecosystems services, natural capital and the use of remote observations will be advantageous.

Supplementary information:
Anecdotally there is an increasing occurrence of extremely lush summer growth of intertidal seagrass meadows in SW England estuaries (e.g. Tamar, Exe, TawTorridge) but with no formal evidence base. Intertidal seagrass is currently ignored in all ecosystem assessments, yet if it has the same potential ecosystem services as the much better understood subtidal seagrass, its recovery and growth may be an environmental good news story.

The project will train the student to take the interdisciplinary approach that is required for natural capital assessment to support management and policy development and implementation. The student will develop expertise in a suite of skills from earth observation image delivery and analysis via satellites and drones, to intertidal fieldwork, benthic ecology, biogeochemistry, through to conceptual thinking on ecosystem services and delivery of the natural capital approach. The student would be a good candidate for the EUMETSAT training courses, which teach all skills required for accessing and processing Sentinel-3 data, as well as boot-camp Python training. These skills are transferable to all EO sensors.

As a PhD student on this project you will receive appropriate training to take a multi and interdisciplinary approach:

  • Using empirical observations from the ground and aerial drone photography you will train models that analyse earth observation (EO) data from satellites to identify intertidal seagrass. You will analyse EO data from the past 15 years, to track the extent of recent development of intertidal seagrass in SW England and other estuaries in the UK.
  • Through case studies in SW England you will explore historical occurrence and possible causes of the development of meadows.
  • Through field sampling in estuaries and laboratory analysis, you will examine the influence of seagrass on the underlying benthic fauna and its functions.
  • You will then quantify potential effects on the flows of ecosystem services, including carbon flows for climate regulation, finally considering the social and economic natural capital implications.
  • A programme for future monitoring of intertidal seagrass through citizen science projects with drones could be an area that is developed.
There may be an option to conduct some studies in SE Asia associated with PML’s ongoing projects in the region.

The student project will be aligned with the NERC SWEEP project on natural capital in SW England, which seeks to create impact from NERC science.

The project will have wider implications for policy and management decisions as it considers implications of local land management and climate change for estuarine coastal ecosystems, recovery of seagrass – a species of high conservation and socio-ecological importance, and the application of the UK governments natural capital approach.

The supervisory team includes EO experts (Biermann), benthic ecology experts (Widdicombe, Austen, Attrill), seagrass expert (Attrill), ecosystem service and natural capital experts (Austen, Attrill), upstream land management and water catchment expert (Laurence Couldrick), conservation, restoration and policy expert (Maggs). All supervisors have extensive experience of working with local and national policy and management delivery bodies.

JNCC, 2019. Unmanned Aerial Vehicles for use in marine benthic monitoring. Marine Monitoring Platform Guidelines No. 3. JNCC, Peterborough, ISSN 2517-7605.

Duffy, J.P., Pratt, L., Anderson, K., Land, P.E. & Shutler, J.D., 2018. Spatial assessment of intertidal seagrass meadows using optical imaging systems and a lightweight drone. Estuarine, Coastal and Shelf Science, 200, pp.169-180.


Broszeit, S., Beaumont, Nicola J., Hooper, Tara L., Somerfield, Paul J., Austen, Melanie C. (2019). Developing conceptual models that link multiple ecosystem services to ecological research to aid management and policy, the UK marine example. Marine Pollution Bulletin 141: 236-243.

Hattam C, Atkins JP, Beaumont N, Bӧrger T, Bӧhnke-Henrichs A, Burdon D, de Groot R, Hoefnagel E, Nunes PA, Piwowarczyk J, Sastre S, Austen MC 2014.

Marine Ecosystem Services: linking indicators to their classification. Ecological Indicators, 49, 61-75 DOI: 10.1016/j.ecolind.2014.09.026.

Hirst, J.A., Attrill, M.J. (2008). Small is beautiful: an inverted view of habitat fragmentation in seagrass beds. Estuarine and Coastal Shelf Science 78: 811–818.

Watson SCL, Beaumont NJ, Widdicombe S, Paterson DM (2019) Comparing the network structure and resilience of two benthic estuarine systems following the implementation of nutrient mitigation actions. Estuarine and Coastal Shelf Science

Sunday JM, Fabricius KE, Kroeker KJ, Anderson KM, Brown NE, Barry JP, Connell SD, Dupont S, Gaylord B, Hall -Spencer JM, Klinger T, Milazzo M, Munday PL, Russell BD, Sanford E, Thiyagarajan V, Vaughan MLH, Widdicombe S, Harley CDG (2017) Ocean acidification can mediate biodiversity shifts by changing biogenic habitat. Nature Climate Change 7(1): 81. DOI: 10.1038/NCLIMATE3161.